Unit 4
Topic 1: Properties and structure of atoms
Subject matter
Structure of organic compounds
recognise that organic molecules have a hydrocarbon skeleton and can contain functional groups,
including alkenes, alcohols, aldehydes, ketones, carboxylic acids, haloalkanes, esters, nitriles,
amines, amides and that structural formulas (condensed and extended) can be used to show the
arrangement of atoms and bonding in organic molecules
deduce the structural formulas and apply IUPAC rules in the nomenclature of organic compounds
(parent chain up to 10 carbon atoms) with simple branching for alkanes, alkenes, alkynes, alcohols,
aldehydes, ketones, carboxylic acids, haloalkanes, esters, nitriles, amines and amides
identify structural isomers as compounds with the same molecular formula but different arrangement
of atoms; deduce the structural formulas and apply IUPAC rules in the nomenclature for isomers of
the non-cyclic alkanes up to C6
identify stereoisomers as compounds with the same structural formula but with different arrangement
of atoms in space; describe and explain geometrical (cis and trans) isomerism in non-cyclic alkenes
Mandatory practical: Construct 3D molecules of organic molecules.
Physical properties and trends
recognise that organic compounds display characteristic physical properties, including melting point,
boiling point and solubility in water and organic solvents that can be explained in terms of
intermolecular forces (dispersion forces, dipole-dipole interactions and hydrogen bonds), which are
influenced by the nature of the functional groups
predict and explain the trends in melting and boiling point for members of a homologous series
discuss the volatility and solubility in water of alcohols, aldehydes, ketones, carboxylic acids and
halides.
Organic reactions and reaction pathways
appreciate that each class of organic compound displays characteristic chemical properties and
undergoes specific reactions based on the functional group present; these reactions, including acid-
base and oxidation reactions, can be used to identify the class of the organic compound
understand that saturated compounds contain single bonds only and undergo substitution reactions,
and that unsaturated compounds contain double or triple bonds and undergo addition reactions
determine the primary, secondary and tertiary carbon atoms in halogenoalkanes and alcohols and
apply IUPAC rules of nomenclature
describe, using equations:
- oxidation reactions of alcohols and the complete combustion of alkanes and alcohols
- substitution reactions of alkanes with halogens
- substitution reactions of haloalkanes with halogens, sodium hydroxide, ammonia and potassium
cyanide
- addition reactions of alkenes with water, halogens and hydrogen halides
- addition reactions of alkenes to form poly(alkenes)
recall the acid-base properties of carboxylic acids and explain, using equations, that esterification is
a reversible reaction between an alcohol and a carboxylic acid
recognise the acid-base properties of amines and explain, using equations, the reaction with
carboxylic acids to form amides
recognise reduction reactions and explain, using equations, the reaction of nitriles to form amines
and alkenes to form alkanes
recognise and explain, using equations, that:
- esters and amides are formed by condensation reactions
- elimination reactions can produce unsaturated molecule and explain, using equations, the
reaction of haloalkanes to form alkenes
understand that organic reactions can be identified using characteristic observations and recall tests
to distinguish between:
- alkanes and alkenes using bromine water
- primary, secondary and tertiary alcohols using acidified potassium dichromate (VI) and
potassium manganate (VII)
understand that the synthesis of organic compounds often involves constructing reaction pathways
that may include more than one chemical reaction
deduce reaction pathways, including reagents, condition and chemical equations, given the starting
materials and the product.
Organic materials: structure and function
appreciate that organic materials including proteins, carbohydrates, lipids and synthetic
polymers display properties including strength, density and biodegradability that can be
explained by considering the primary, secondary and tertiary structures of the materials.
Describe and explain the primary, secondary (α-helix and β-pleated sheets), tertiary and
quaternary structure of proteins.
Recognise that enzymes are proteins and describe the characteristics of biological catalysts
(enzymes) including that activity depends on the structure and the specificity of the enzyme
action.
Recognise that monosaccharides contain either an aldehyde group (aldose) or a ketone group
(ketose) and several –OH groups, and have the empirical formula CH2O.
Distinguish between α-glucose and β-glucose, and compare and explain the structural
properties of starch (amylose and amylopectin) and cellulose
Recognise that triglycerides (lipids) are esters and describe the difference in structure between
saturated and unsaturated fatty acids.
Describe, using equation, the base hydrolysis (saponification) of fats (triglycerides) to produce
glycerol and its long chain fatty acid salt (soap), and explain how their cleaning action and
solubility in hard water is related to their chemical structure.
Explain how the properties of polymers depends on their structural features including; the
degree of branching in polyethane (LDPE and HDPE), the position of the methyl group in
polypropene (syntactic, isotactic and atactic) and polytetrafluorethene.
Analytical techniques
Explain how proteins can be analysed by chromatography and electrophoresis.
Select and use data from analytical techniques, including mass spectrometry, x-ray
crystallography and infrared spectroscopy, to determine the structure of organic molecules.
Analyse data from spectra, including mass spectrometry and infrared spectroscopy, to
communicate conceptual understanding, solve problems and make predictions.
Topic 2: Chemical synthesis and design
Subject matter
Chemical synthesis
Appreciate that chemical synthesis involves the selection of particular reagents to form a
product with specific properties
Understand that reagents and reaction conditions are chosen to optimise the yield and
rate for chemical synthesis processes, including the production of ammonia (Haber
process), sulphuric acid (contact process) and biodiesel (base-catalysed and lipase-
catalysed methods)
Understand that fuels, including biodiesel, ethanol and hydrogen, can be synthesised
from a range of chemical reactions including addition, oxidation and esterification
Understand that enzymes can be used on an industrial scale for chemical synthesis to
achieve an economically viable rate, including fermentation to produce ethanol and
lipase-catalysed transesterification to produce biodiesel
Describe, using equations, the production of ethanol from fermentation and the
hydration of ethene
Describe, using equations, the transesterification of triglycerides to produce biodiesel
Discuss, using diagrams and relevant half-equations, the operation of a hydrogen fuel cell
under acidic and alkaline conditions
Calculate the yield of chemical synthesis reactions by comparing stoichiometric
quantities with actual quantities and by determining limiting reagents.
Green chemistry
Appreciate that green chemistry principles include the design of chemical synthesis
processes that use renewable raw materials, limit the use of potentially harmful solvents
and minimise the amount of unwanted products
Outline the principles of green chemistry and recognise that the higher the atom
economy, the ‘greener’ the process
Calculate atom economy and draw conclusions about the economic and environmental
impact of chemical synthesis processes
Macromolecules: polymers, proteins and carbohydrates
Describe, using equations, how addition polymers can be produced from their monomers
including polyethene (LDPE and HDPE), polypropene and polytetrafluoroethylene
Describe, using equations, how condensation polymers, including polypeptides
(proteins), polysaccharides (carbohydrates) and polyesters, can be produced from their
monomers
Discuss the advantages and disadvantages of polymer use, including strength, density,
lack of reactivity, use of natural resources and biodegradability
Describe the condensation reaction of 2-amino acids to form polypeptides (involving up
to three amino acids), and understand that polypeptides (proteins) are formed when
amino acid monomers are joined by peptide bonds.
Describe the condensation reaction of monosaccharides to from disaccharides (lactose,
maltose and sucrose) and polysaccharides (starch, glycogen and cellulose), and
understand that polysaccharides are formed when monosaccharide monomers are
joined by glycosidic bonds.
Molecular manufacturing
Appreciate that molecular manufacturing processes involve the positioning of molecules
to facilitate a specific chemical reaction; such methods have the potential to synthesis
specialised products, including proteins, carbon nanotubes, nanorobots and chemical
sensors used in medicine.
